What is a specialised nerve cell ?

Appeared in: RRB Staff Nurse Ahmedabad-2015

Explanation

A neuron is defined as the structural and functional unit of the nervous system.
It is a specialized cell responsible for receiving, processing, and transmitting information through electrical and chemical signals.
A complete neuron consists of a cell body (soma), dendrites (which receive signals), and an axon (which transmits signals).

Option B: An axon is a long, slender projection of a nerve cell, not the entire cell itself. It is a component of a neuron responsible for conducting electrical impulses away from the cell body.
Option C: Dendrites are branched, tree-like extensions of a nerve cell, not the entire cell. They are specialized to receive signals from other neurons.
Option D: The nucleus is an organelle found within the neuron's cell body that contains the cell's genetic material. It is a critical component of the cell, but not the specialized cell itself.

Visual 1: Diagram - A labeled diagram of a neuron, clearly showing the cell body (soma), nucleus, dendrites, axon, myelin sheath, and axon terminals. This helps visualize all the components mentioned in the options and their relationship to each other.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Structure and function of a neuron as background academic context rather than a clinical decision trigger.
Understanding the structure of a neuron is fundamental to comprehending neurological disorders. Diseases like Multiple Sclerosis (MS) involve damage to the myelin sheath of the axon, which disrupts the efficient transmission of nerve signals.
What if? If a patient has a neurodegenerative disease that specifically causes the loss of dendrites, the primary deficit would be in receiving and integrating information from other neurons, leading to cognitive or sensory impairments, rather than a primary failure in signal transmission along the axon.

How to Approach the Question

Identify the core concept in the question: 'specialised nerve cell'. This asks for the name of the fundamental cell type in the nervous system.
Analyze the options to determine their relationship to a nerve cell.
Recall the basic definition of a 'Neuron' as the primary functional unit of the nervous system.
Differentiate between the whole cell (Neuron) and its constituent parts (Axon, Dendrites) or organelles (Nucleus).
Conclude that 'Neuron' is the only option that represents the entire specialized cell, while the others are just parts of it.

Concept Tested & Keywords

QtLVmcUcjMJ8Vr7jWwPjB6

Practise the full RRB Staff Nurse Ahmedabad-2015

Attempt every question from this paper in a timed mock, then review the full solution for each one.